Comment the weird behavior of __has_feature(is_empty) and __has_feature(is_pod)
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@136788 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/PPMacroExpansion.cpp b/lib/Lex/PPMacroExpansion.cpp
index 7046c5f..a4b6cc9 100644
--- a/lib/Lex/PPMacroExpansion.cpp
+++ b/lib/Lex/PPMacroExpansion.cpp
@@ -639,6 +639,10 @@
.Case("is_base_of", LangOpts.CPlusPlus)
.Case("is_class", LangOpts.CPlusPlus)
.Case("is_convertible_to", LangOpts.CPlusPlus)
+ // __is_empty is available only if the horrible
+ // "struct __is_empty" parsing hack hasn't been needed in this
+ // translation unit. If it has, __is_empty reverts to a normal
+ // identifier and __has_feature(is_empty) evaluates false.
.Case("is_empty",
LangOpts.CPlusPlus &&
PP.getIdentifierInfo("__is_empty")->getTokenID()
@@ -646,6 +650,10 @@
.Case("is_enum", LangOpts.CPlusPlus)
.Case("is_literal", LangOpts.CPlusPlus)
.Case("is_standard_layout", LangOpts.CPlusPlus)
+ // __is_pod is available only if the horrible
+ // "struct __is_pod" parsing hack hasn't been needed in this
+ // translation unit. If it has, __is_pod reverts to a normal
+ // identifier and __has_feature(is_pod) evaluates false.
.Case("is_pod",
LangOpts.CPlusPlus &&
PP.getIdentifierInfo("__is_pod")->getTokenID()